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Date:   Thu, 22 Apr 2021 18:53:28 -0700 (PDT)
Subject:     Re: [PATCH] riscv/mm: Use BUG_ON instead of if condition followed by BUG.
In-Reply-To: <1617112588-7750-1-git-send-email-zhouchuangao@vivo.com>
CC:     Paul Walmsley <paul.walmsley@sifive.com>, aou@eecs.berkeley.edu,
        Atish Patra <Atish.Patra@wdc.com>,
        Anup Patel <Anup.Patel@wdc.com>, rppt@kernel.org,
        akpm@linux-foundation.org, wangkefeng.wang@huawei.com,
        zong.li@sifive.com, mick@ics.forth.gr,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        zhouchuangao@vivo.com
From:   Palmer Dabbelt <palmer@dabbelt.com>
To:     zhouchuangao@vivo.com
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On Tue, 30 Mar 2021 06:56:26 PDT (-0700), zhouchuangao@vivo.com wrote:
> BUG_ON() uses unlikely in if(), which can be optimized at compile time.
>
> Signed-off-by: zhouchuangao <zhouchuangao@vivo.com>
> ---
>  arch/riscv/mm/init.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
> index 067583a..a7fa5e2 100644
> --- a/arch/riscv/mm/init.c
> +++ b/arch/riscv/mm/init.c
> @@ -213,8 +213,8 @@ static phys_addr_t alloc_pte_late(uintptr_t va)
>  	unsigned long vaddr;
>
>  	vaddr = __get_free_page(GFP_KERNEL);
> -	if (!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)))
> -		BUG();
> +	BUG_ON(!vaddr || !pgtable_pte_page_ctor(virt_to_page(vaddr)));
> +
>  	return __pa(vaddr);
>  }

Thanks, this is on for-next.